Problem came back

Yes must be your soil is quite heavily fertilised. 🌱👍

With the leaf edges curling up it looks like light or heat stress . That will cause brown spots like that .

The most common signs of Potassium deficiency is the browning or yellowing of the leaf tips and edges such as this. Brown spots on the leaves are the next symptoms to follow. Before making any changes to your schedule ensure temp is not to high, double check ph of water and avoid over fertilization/salt buildups as not to lock out nutrients.

Looks like some mag def.. I'd try supplementing some cal mag in. Hope this helps! Happy growing! 👊